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Muscular System Isabella Sandoval period 5 - Coggle Diagram
Muscular System
Isabella Sandoval
period 5
Major functions the muscular system
Movement- Skeletal muscles pull on the bones causing movements at the joints
Support- Muscles of the body wall support the internal organs.
Protection- Skeletal muscles, particularly of the body wall, cushion the body's internal organs from force applied to the exterior of the body.
Heat generation- Heat is a waste product of muscle metabolism, which helps maintain an internal body temperature of 98.6 F.
Blood Circulation- Cardiac muscles aid pumping action of the heart by aiding blood circulation.
3 types of muscles and their functions
skeletal muscle-enable humans to move and perform daily activities
smooth muscle- helps with digestion and nutrient collection
cardiac muscle- responsible for the contractility of the heart and, therefore, the pumping action
Names of all the skeletal muscles
bicep brachii
brachialis
brachioradialis
deltoid
external obliques
flexor carpi ulnaris
frontails
Ilipsoas
masseter
orbicularis oris
orbicularis oculi
palmaris longus
pectinus
pectoralis major
pronator teres
rectus abdormis
serrates anterior
sternocleidomastoid
sternohyoid
temporalis
tensor fasciae latae
trapezius
tricep brachii
zygomaticus
anterior/inferior view
adductor longus
fibulas longus
extensor digitorum longus
gastrocnernius
gracilis
Iliotibial tract
rectus femoris
sartorius
soleus
Sarcomere
The fundamental repeat unit within muscle that is responsible for contraction is the sarcomere
. A sarcomere is composed of two main protein filaments, thin actin and thick myosin filament, which are the active structures responsible for muscular contraction.
Neuromuscular junction
events that lead up to neuromuscular
1) An AP travels down the axon. to the axon terminal
2) Electrical gated calcium channels open
3) Calcium causes the vesicles to
4) ACH diffuses across the synaptic cleft
5) ACH binding opens ion channels
6) If the muscle reaches the threshold (-55mv) at the motor end plate
7) ACH is broken down by
Sliding filament theory of muscle contraction
a muscle fiber contracts when myosin filaments pull actin filaments closer together and thus shorten sarcomeres within a fiber.
Step 1: Calcium ions. Calcium ions are released by the sarcoplasmic reticulum in the actin filament
Step 2: cross bridge forms
Step 3: Myosin head slides
Step 4: skeletal muscle contraction has occurred
Step 5: Cross bridge breaks
Step 6: troponin
Action potential in a muscle fiber
The muscle action potential triggers a sequence of actions that ultimately results in the contraction and relaxation of the muscle fiber. This sequence is called the excitation–contraction–relaxation cycle.
Muscle coverings
The outermost connective tissue sheath surrounding the entire muscle is known as epimysium. The connective tissue sheath covering each fasciculus is known as perimysium, and the innermost sheath surrounding individual muscle fiber is known as endomysium.
Disorders associated with the Muscular system
Amyotrophic lateral sclerosis (ALS)
Charcot-Marie-Tooth disease.
Multiple sclerosis.
Muscular dystrophy.
Myasthenia gravis.
Myopathy.
Myositis, including polymyositis and dermatomyositis.
Peripheral neuropathy.